Trains.com

ZW Shorting Out

2078 views
9 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    January 2006
  • 193 posts
ZW Shorting Out
Posted by gottcent on Wednesday, February 6, 2013 4:34 PM

A friend has asked me to look at his postwar 275 watt ZW, because it has started shorting out when two or more trains are run on it for just a few minutes. I tested it out with several of my own engines which I know to be in good shape, and he's right: run two or more and after about 2 minutes the red "short" light comes on and everything stops. Let the transformer cool for a few seconds (maybe 30) and it pops back on, only to repeat the symptom again. It doesn't seem to matter which of the four circuits you're hooked up to--happens with all of them. One train runs fine, but two or more cause this problem. Any thoughts?

  • Member since
    July 2003
  • From: US
  • 1,380 posts
Posted by Curmudgeon on Wednesday, February 6, 2013 5:05 PM

It's not shorting...probably.

The circuit breaker is tripping, giving you a "short circuit" indicator.

Breaker is going bad.

Replace it.

Usual suspects have them.

At least, that's what I'd do first.

  • Member since
    June 2004
  • From: Orig: Tyler Texas. Lived in seven countries, now live in Sundown, Louisiana
  • 25,640 posts
Posted by jeffrey-wimberly on Wednesday, February 6, 2013 5:27 PM

Curmudgeon

Breaker is going bad.

Replace it.

Indeed, start with the cheapest fix and work up.

Running Bear, Sundown, Louisiana
          Joined June, 2004

Dr. Frankendiesel aka Scott Running Bear
Space Mouse for president!
15 year veteran fire fighter
Collector of Apple //e's
Running Bear Enterprises
History Channel Club life member.
beatus homo qui invenit sapientiam


KRM
  • Member since
    January 2011
  • From: North Bluff above Marseilles IL
  • 6,418 posts
Posted by KRM on Wednesday, February 6, 2013 6:50 PM

Curmudgeon

It's not shorting...probably.

The circuit breaker is tripping, giving you a "short circuit" indicator.

Breaker is going bad.

Replace it.

Usual suspects have them.

At least, that's what I'd do first.

 Not knowing how old it is or what breaker it has in it I agree circuit breaker is tripping.

Joined 1-21-2011    TCA 13-68614

Kev, From The North Bluff Above Marseilles IL. Whistling

 

  • Member since
    December 2012
  • 7 posts
Posted by Koala on Thursday, February 7, 2013 12:14 AM

Sounds like the circuit breaker.  There are two types.  One is mounted to the side of the frame and the other is mounted to the base of the housing.  I think these were made by Klixon.  The base version and some of the frame versions have an adjustment screw.  Try adjusting the screw first and then test the unit.  I use an ammeter in series with some old car headlamps to put a load on the transformer.  I adjust the breaker to hold 12 amps and then open if it goes higher.  If all else fails just replace the breaker.  Both are available from parts dealers for about  $15.  Good luck.

  • Member since
    January 2001
  • From: Colchester, Vermont
  • 1,136 posts
Posted by Kooljock1 on Thursday, February 7, 2013 4:02 AM

http://lioneltransformer.com/

Jon Cool

Now broadcasting world-wide at http://www.wkol.com Weekdays 5:00 AM-10:00AM!
  • Member since
    January 2006
  • 193 posts
Posted by gottcent on Thursday, February 7, 2013 8:52 AM

Thanks, guys. I'll look into the circuit breaker and get back to you.

John

  • Member since
    January 2006
  • 193 posts
Posted by gottcent on Thursday, February 7, 2013 5:39 PM

I found the circuit breaker on the side of the frame as you said, but it does not have an adjusting screw. I tried bending it by hand just a bit to make closer contact when closed. Now things run fine, but--lacking an ammeter--I have no way of knowing whether I've closed the contacts too far so that they won't open with a real short. I tried deliberately shorting out one circuit for about 12 seconds but stopped when smoke appeared. The breaker did not open, nor did the red light come on. I'm thinking maybe it would be wiser to invest in a new breaker, which I find on ebay for $12. Looks like a pretty simple swap-out. If you have any other thoughts, let me know.

Thanks, John.

KRM
  • Member since
    January 2011
  • From: North Bluff above Marseilles IL
  • 6,418 posts
Posted by KRM on Thursday, February 7, 2013 6:07 PM

The breaker did not open, nor did the red light come on. I'm thinking maybe it would be wiser to invest in a new breaker, which I find on ebay for $12. Looks like a pretty simple swap-out. If you have any other thoughts, let me know.

 

That is the problem then.  So  Do it!  Yes

Joined 1-21-2011    TCA 13-68614

Kev, From The North Bluff Above Marseilles IL. Whistling

 

  • Member since
    July 2003
  • From: US
  • 1,380 posts
Posted by Curmudgeon on Friday, February 8, 2013 11:26 AM

Sometimes I have to just sit back and be silent.

Now you see. When you "adjust" a circuit breaker without some way of testing it for functionality, you have overcome the protection of said device.

Yeah, you can short the output....but where does it trip? You need an AC ammeter, a variable load, and you need to know what the original design criteria was.

You just replace it and leave any adjustments alone.

Join our Community!

Our community is FREE to join. To participate you must either login or register for an account.

Search the Community

FREE EMAIL NEWSLETTER

Get the Classic Toy Trains newsletter delivered to your inbox twice a month